Abstract
Inhibition of basolateral Na+/K+ ATPase by ouabain eventually abolishes transport of glucose. The present study was performed to test, if this effect is due to a dissipation of the electrochemical gradient for sodium or due to a regulatory inhibition of sodium-coupled glucose entry across the luminal membrane at increasing intracellular sodium activity. To this end, proximal convoluted tubules of the doubly perfused isolated frog kidney were perfused alternatively with solutions containing either 5 mmol/l glucose or raffinose. The potential difference across the peritubular cell membrane (PDpt) and across the epithelium (PDpt) has been recorded with conventional and across the peritubular cell membrane with ion selective microelectrodes (PDpt). In the absence of luminal glucose PDpt is (±SEM) −54.0±2.4 mV, PDte=−1.2±2.0 mV and PD Napt =−96±5 mV. The electrochemical gradient for sodium (μNa+) amounts to 95 mV and intracellular sodium activity to 14 mmol/l (extracellular sodium activity is 74 mmol/l). Luminal application of glucose leads to a rapid depolarisation of PDpt (ΔPDpt=8.6±0.9 mV and PD Napt (ΔPD Napt =11.1±3.0 mV) and to hyperpolarisation of PDte (ΔPDte=−0.8±0.2 mV). The peritubular application of ouabain leads to a gradual, reversible and proportional decline of PDpt, PD Napt and μNa+. Glucose induced ΔPDpt and ΔPD Napt decrease in parallel to PDpt and PD Napt , resp. In a separate series, the lumped conductance (G m) of the luminal and basolateral cell membrane has been determined, which amounts to 2.4±0.3 μS/mm (tubule length).G m decreases 23±4%, when PDpt is decreased to half. ΔPDpt andG m allow the calculation of an apparent transport rate (T Glu). Following the application of ouabain,T Glu decreases in linear proportion to PDpt and PD Napt . There is no evidence for a significant regulatory inhibition ofT Glu. Rather, glucose transport operates in linear proportion to the potential difference across the luminal membrane.
Similar content being viewed by others
References
Anagnostopoulos T, Velu E (1974) Electrical resistance of cell membranes in necturus kidney. Pflügers Arch 346:327–339
Aronson PS, Sacktor B (1975) The Na+ gradient-dependent transport ofD-glucose in renal brush border membranes. J Biol Chem 250:6032–6039
Aronson PS, Hayslett JP, Kashgarian M (1979) Dissociation of proximal tubular glucose and Na+ reabsorption by amphotericin B. Am J Physiol 236:F392-F397
Barrett PQ, Aronson PS (1982) Glucose and alanine inhibition of phosphate transport in renal microvillus membrane vesicles. Am J Physiol 242:F126-F131
Busse D, Jahn A, Steinmaier G (1975) Carrier-mediated transfer ofD-glucose in brush border vesicles derived from rabbit renal tubules. Biochim Biophys Acta 401:231–243
Crane RK (1977) The gradient hypothesis and other models of carrier-mediate active transport. Rev Physiol Biochem Pharmacol 78:101–159
Frömter E (1982) Electrophysiological analysis of rat renal sugar and amino acid transport. I. Basic phenomena. Pflügers Arch 393:179–189
Frömter E, Geßner K (1974) Active transport potentials, membrane diffusion potentials and streaming potentials across rat kidney proximal tubule. Pflügers Arch 351:85–98
Guder WG, Wirthensohn G (1981) Renal turnover of substrates. In: Greger R, Lang F, Silbernagl S (eds) Renal transport of organic substances. Springer, Berlin Heidelberg New York, pp 66–77
Guggino WB, Boulpaep EL, Giebisch G (1982) Electrical properties of chloride transport across the Necturus proximal tubule. J Membr Biol 65:185–196
Guggino WB, Windhager EE, Boulpaep EL, Giebisch G (1982) Cellular and paracellular resistances of the Necturus proximal tubule. J Membr Biol 67:143–154
Hilden S, Sacktor B (1982) Potential-dependentD-glucose uptake by renal brush border membrane vesicles in the absence of sodium. Am J Physiol 242:F340-F345
Hopfer U, Groseclose R (1980) The mechanism of Na+-dependentD-glucose transport. J Biol Chem 255:4453–4462
Lee CO, Armstrong WD (1972) Activities of sodium and potassium ions in epithelial cells of small intestine. Science 173:1261–1264
Maruyama T, Hoshi T (1972) The effect ofD-glucose on the electrical potential profile across the proximal tubule of newt kidney. Biochim Biophys Acta 282:214–225
Misfeldt DS, Sanders MJ (1981) Transepithelial glucose transport in cell culture. Am J Physiol 240:C92-C95
Planelles G, Anagnostopoulos T (1982) Effects of ouabain on the electrophysiological properties of proximal tubular cells. J Pharmacol Exp Ther 223:841–847
Samarzija I, Hinton BT, Frömter E (1982) Electrophysiological analysis of rat renal sugar and amino acid transport. II. Dependence on various transport parameters and inhibitors. Pflügers Arch 393:190–197
Schultz SG (1977) Sodium-coupled solute transport by small intestine: a status report. Am J Physiol 233(4):E249-E254
Schultz SG (1981) Homocellular regulatory mechanisms by sodium-transporting epithelia: avoidance of extinction by “flush-through”. Am J Physiol 241:F579–590
Steiner RA, Oehme M, Ammann D, Simon W (1979) Neutral carrier sodium ion-selective microelectrode for intracellular studies. Anal Chem 51:351–353
Taylor A, Windhager EE (1979) Possible role of cytosolic calcium and Na-Ca exchange in regulation of transepithelial sodium transport. Am J Physiol 236:F505-F512
Thierry J, Poujeol P, Pipoche P (1981) Interactions between Na+-dependent uptake ofD-glucose, phosphate andL-alanine in rat renal brush border membrane vesicles. Biochim Biophys Acta 647:203–210
Turner RJ, Moran A (1982) Stoichiometric studies of the renal outer cortical brush border membraneD-glucose transporter. J Membr Biol 67:73–80
Turner RJ, Silverman M (1977) Sugar uptake into brush border vesicles from normal human kidney. Proc Natl Acad Sci USA 74:2825–2829
Ullrich KJ (1979) Sugar, amino acid, and Na+ cotransport in the proximal tubule. Ann Rev Physiol 41:181–195
Ullrich KJ, Rumrich G, Klöss S (1974) Specificity and sodium dependence of the active sugar transport in the proximal convolution of the rat kidney. Pflügers Arch 351:35–48
Ullrich KJ, Capasso G, Rumrich G, Papavassiliou F, Klöss S (1977) Coopling between proximal tubular transport processes. Studies with ouabain, SITS and HCO −3 -free solutions. Pflügers Arch 368:245–252
Walker JL (1971) Ionic specific liquid ion-exchanger micro-electrodes. Anal Chem 43:89A-93A
Wang W, Oberleithner H, Lang F (1983) The effect of cAMP on the cell membrane potential and intracellular ion activities in proximal tubule of rana esculenta. Pflügers Arch 396:192–198
Windhager EE, Boulpaep EL, Giebisch G (1967) Electrophysiological studies on single nephrons. In: Proc 3rd Int Congr Nephrol, Washington. Karger, Basel New York, pp 35–47
Author information
Authors and Affiliations
Additional information
This study has been supported by Österr. Forschungsrat, Proj. No. 4366
Rights and permissions
About this article
Cite this article
Lang, F., Messner, G., Wang, W. et al. The influence of intracellular sodium activity on the transport of glucose in proximal tubule of frog kidney. Pflugers Arch. 401, 14–21 (1984). https://doi.org/10.1007/BF00581527
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00581527